London CNN  —  Britain will toughen its requirements for legal migrants and extend the wait for newcomers to claim citizenship, Prime Minister Keir Starmer said Monday, announcing a slew of policy changes as he resists a political barrage from the country’s emboldened populist right. Immigrants will now have to wait up to 10 years before they can seek to become British citizens – raised from five years – and requirements surrounding their skills level and proficiency in English will be raised,